The present invention generally relates to gas fired water heaters, and more specifically, to self powered, either forced or induced draft, gas fired water heaters having a thermoelectric module and a through-chamber heat sink.
A gas fired water heater generally has an insulated tank for storing hot water. Cold water supplied to the tank is heated by a flame produced by a natural gas burner operating at atmospheric pressure. The combustion products produced by the burner are removed by a natural draft chimney. In a typical home, the chimney is shared with a gas furnace.
In the future, however, most gas furnaces may not need a chimney. Powered gas furnaces may be necessary to meet lowering emission standards and increasing efficiency mandates. Powered devices have an electric fan or blower to propel the combustion air through the gas burner and obtain more complete combustion and extract more heat from the combustion products in a heat exchanger. Because the blower provides the draft and the temperature of the combustion products leaving the furnace is relatively low, the furnace can be vented through the wall.
In existing homes, the chimney will become oversized if the water heater is operating alone. An oversized chimney can result in inadequate draft and condensation leading to corrosion and structural damage. Thus, a chimney liner could be required, or the chimney could be required to be blocked off and the gas water heater replaced with a powered unit that can be vented through the wall. Additionally, more stringent emission standards and increasing efficiency mandates may necessitate powered water heaters. Powered water heaters, therefore, may become desirable because of the absence of a chimney or the presence of a standard or mandate.
Gas water heaters are desirable because of low operating cost and a short recovery rate of initial and installed costs. The need for an electrician to hard wire powered gas water heaters, however, would significantly increase the installation cost of gas water heaters. A self-powered gas water heater could eliminate the need for hard wiring and keep the low operating cost of a gas water heater available for the homeowner.
Therefore, it is an objective of the present invention to provide a powered water heater that does not require hard wiring for electrical power. It is also an objective of the present invention to provide a powered water heater having low initial and installed costs. It is a further objective of the present invention to provide a powered water heater having a thermoelectric module under conditions sufficient to provide all operating power. It is also the objective of this invention to provide a self-powered water heater that is easily repaired or maintained.